Counterbalance



1932' T. o. DUCKWORTH ET AL I 0 COUNTERBALANCE Filed Jan. 9. 1951 v Patented Oct. 4, 1932 UNITED STATES PATENT OFFICE THEOPHIUS O. DUGKWORTH AND FRANCIS L. HORSPOOL, OF SALT LAKE CITY, UTAH COUNTEBBALANCE Application, filed January 9, 1931. Serial No. 507,636.

abolish the heavy dangerous weights now used on the working-beam and to give more balancing power than the weights now used. Another object of this invention is to place all operating parts within an air'tank in such a manner that air within the tank will enter a cylinder within the tank and operate as a counter balance for any weight that may be placed on the working beam.

Another object of this invention is to provide a counter balance with a self operating air pump placed in such a manner that the operating of the working beam will operate the pump to supply new air for all air leakage that may leak out of the tank in the operation thereof.

Another object of this invention is to provide an air counter balance, comprising a cylinder having a piston therein with 'which an air cushion can be placed against the inner face of the piston in the lowering of the weight of the load and to place an air pressure against the inner face of the piston in the lifting of the load.

With these and other objects in view the invention consists of the following novel construction as hereinafter described and claimed. i i

In the accompanying drawing forming a part of this specification and in which corresponding parts are denoted by like reference characters, is illustrated the preferred form of embodiment of the invention, capable of carrying the same into practical operation, it being understood that the invention is not necessarily limited thereto, as various changes in shape, proportion and general assemblage of its parts may be resorted to without departing from the principles of the invention, or sacrificing any of its advantages, and the right is therefore reserved for making all the changes and modifications which will fall within the scope of the invention and claim made therefor.

The invention will be described as applied to the standard working beam now used on wells for a pump rod lift.

Referring to the drawing; Figure 1 1s a vertical section view of the invention A. a a

Fig. 2 is a small size plan view through line 2-2 Fig. 1 showing the lay of the cylinders 2 and 3.

The reference character A denotes the invention, B the support for the working beam C, D the motor for driving the crank E, F a rod for pivotally connecting the crank E to the working beam C. G is the pump rod in the well H which is connected to the I working beam C.

The invention comprises in combination with a working beam pump rod lift C. A tank 1, cylinders 2 and 3 placed through the upper head 10 of the tank.

The cylinder 2 the-lower end thereof/resting upon the bottom of the tank has apertures 8 therein through which air passes from the tank to the cylinder to balance the piston 4. As the motor D operates the working beam to lower the piston, the air in the cylin der is moved through apertures 8 into the tank. And as the piston is raised air from the tank passes through the apertures into the cylinder 2. Thus when the required amount of pressure of air is in the tank it will always maintain the piston 4 in balance, so it will require a very small amount of power to operate the working beam. The upper end of the cylinder 2 is welded into the tank head 10 so no air can escape thereb The piston 4 is pivotally attached to the rod 6 at 5 thus allowing the rod to swing freely with the movement of the working beam.

The cylinder .3 has a collar 15 secured near I the upper end thereof. The collar is threaded within the tank head 10 in such a manner that the cylinder may be removed at will and when the collar is threaded into the tank head 10 the movement of the piston. In the lower end of the cylinder is an aperture 17 through wh1ch air is forced by the downward stroke of the piston 11 into the tank. The piston 11 is pivotally secured to rod 13 at 12 and the upper end of the rod 13 is pivotally connected to the working beam at 14, thus as the working beam is operated the piston will be operated in parallel relation to piston 4, as the piston 11 is moved upward or outward air is .drawn or passes by the sides thereof into the opening below the piston by the contraction of the leather on the piston. And as the piston is' lowered the air is forced through the aperture 17 into the tank. Another pump 23 is used to fill the tank with air before the operation of the working beam by the motor D.

The cylinder 3 is known as a pump cylinder while cylinder 2 is known as a counterbalance cylinder which will overcome all weight of the pump rod and liquid in the well.

The pump cylinder 3 is used to supply all air that may leak out of the tank in the operagage tion of the counter-balance piston 4.

On the bottom of the cylinder 3 is placed pins 18 over which is placed a valve 16 which fits up to the aperture 17 and is secured there in place by springs 19 that are secured onto the pins 18 by nuts 20, thus by the pressure of air in the tank with the spring tension against the valve 12 there will be no air leakage from the tank into the pump on the lifting of the piston 11.

On the top ofthe tank is placed a pressure 21 and a safety valve 22. i

The rod 6 is pivotally connected tothe walking beam Cat 7.

To illustrate the operation of the invention for counter balancing the load. Say it is 11,500 pounds that the motor D has to lift without a counter balance.

The tank being filled with air to one hundred pounds to the square inch. The piston 4 being twelve inches in diameter will have 113, square inches, times 100 will equal 11.300 pressure on the inner face of the piston 4 thus the motor D will only have to lift or lower 200 pounds this being the required pull on the motor to hold the weight on balance and another pull of ten pounds will move the pump rod up and down. If the air pressure was the requlred weight to hold the piston 4 in balance the motor would only have to give a pull of 10 pounds to. move the rod Gup or down.

The air pressure in the tank is decreased a few pounds when the piston 4 is raised above center or off of balance, and the air pressure is increased a few pounds when the piston 4 is moved below center. The drawmg Flg. 1 shows the pistons on center or on balance, which it will be when the working beam is at rest.

Having thus described the invention what we claim as new and desire to secure by Letters Patent, is;

An air counter balance for a. .pump rod compr sing a base, a sampson post fixed to said base, a walking beam pivoted to said sampson post and attached to said pump rod, a storage tank on said base, a counterbalancng c linder in said tank, a supply cylinder n said tank, the ends of said cylinders bemg in communication with the interior of said tank, pistons in said cylinders and means gonnecting the pistons with the walking cam.

THEOPHIUS O'. DUCKWORTH. FRANCIS L. HORSPOOL. 

